1. Field
The disclosed concept pertains generally to components for electric power systems. The disclosed concept also pertains to methods of determining whether a power circuit in an electric power system is open or closed.
2. Background Information
Electric power systems incorporate switches for control and protection purposes. Distribution systems, which form part of an overall electric power system, include main and branch power buses and circuit breakers mounted in metal cabinets to form switchgear. Interruption of current flow in the buses of the distribution system by a circuit breaker creates an arc as the contacts of the circuit breaker open. These arcs caused by interruption are contained and extinguished in the normal course of operation of the circuit breaker.
At times, however, unintended arcing faults can occur within switchgear cabinets, such as between power buses, or between a power bus and a grounded metal component. Such arcing faults can produce high energy gases, which pose a threat to the structure and nearby personnel. This is especially true when maintenance is performed on or about live power circuits. Frequently, a worker inadvertently shorts out the power bus, thereby creating an arcing fault inside the enclosure. The resulting arc blast creates an extreme hazard and could cause injury or even death. This problem is exacerbated by the fact that the enclosure doors are typically open for maintenance.
There are disconnect switches intended to isolate portions of an electric power system for maintenance that do not allow for indication of open or closed power circuit status by a user in locations readily visible to a user. Because of this, accessing energized electrical equipment is more dangerous.
There is room for improvement in components for electric power systems.
There is also room for improvement in methods of determining whether a power circuit in an electric power system is open or closed in cases where the switch contacts are not directly visible by a user.